Sandpapering-machine.



No. 705,232. Patented July 22, I902. J. A. HALLDEN.

SANDPAPERING MACHINE (Appliation filed Sept. 6, 1901.)

3 Sheets Sheet I.

(I0 Modal.)

VII .11 E 5 5 E5 M/Q/WM N0. 705,232. Patented July 22, IQUZ.

J. A. HALLDEN.

SANDPAPERING MACHINE.

(Application filed Sept. 6, 1901.) (No Model.)

3 Sheets-Sheet 2.

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THE norms PETERS co. mom-ummwuuyamn,

No. 705,232. Patented July 22, I902.

' J. A. HALLDEN.

SANDPAPERING MACHINE.

(Application filed Sept. 6. 1901.)

3 Sheets-Sheet 3.

(No Model.)

FFICE.

JOHN A. HALLDEN, OF ROCKFORD, ILLINOIS, ASSIGNOR OF ONE-THIRD TO ENOCI'ICARLSON, OF CHICAGO, ILLINOIS.

SANDPAPERING-MACHINE.

SPECIFICATION formingpart of Letters Patent N 0. 705,232, dated July 22,1902.

Application filed September 6, 1901. Serial No, 74,508. (No model.)

To aZZ whom it may concern.-

Be it known that I, JOHN A. HALLDEN,'a citizen of the United States,residing at Rock ford, in the county of Winnebago and State of Illinois,have invented certain new and useful Improvements inSandpapering-Machines, of which the following is: a specification.

The object of this invention is the production of an improvedsandpapering-machine. In the accompanying drawings, Figure 1 is a sideelevation of a sandpapering-machine embodyingthe featuresof myinvention.Fig. 2 is a top plan view of said machine. Fig. 3 I5 is a section ondotted line 3 3 of Fig.1, showing the mechanism for shifting the beltsthat move the sandpapering device bodily forward and backward upon thework-table. Fig. 4 is a front elevation, partly in section, of the yokefor supporting the sandpapering device.

Fig. 5 is a perspective View of said yoke, to-

gether with a portion of the frame upon which the yoke is mounted. Fig.6 is a detached view of the san dpapering-roller and its bearing-shaft.Fig. 7 is a perspective View illustrating a form of the sandpaperingdevice adapted to finish fiat surfaces. Fig. 8 is a side elevation ofthe sandpapering device illustrated in the last-preceding figure withthe eccentrics and eccentric-rods for reciprocating the rubbing-blocksof said sandpapering device. Fig. 9 is a top plan view of a sandpaperingmachine equipped with the rubbers shown in the two last-precedingfigures. showing the upper trunnion-joint between the upright tiltingframe and the forwardlyeXt-ending arm which carries the sandpaperingdevice. Fig. 11 is a similar view, partly in section, of the pivotaljoint between the supporting-frame and the lower end of the tiltingframe. Fig. 12 illustrates the forward end of one of the eccentric-rods.

Like letters of reference indicate corresponding parts throughout theseveral views.

In the embodiment herein shown and described of this invention I providea supporting-frame having a work-table thereon. An upwardly-extendingtilting frame is pivotally 50 mounted upon the supporting-frame rearwardof the work-table, and at its upper or Fig. 10 is a fragmental top planview.

end of the screw-threaded shaft A free end carries a pivoted arm towhich the sandpapering device is connected. A screwthreaded shaft isrotatably mounted within said supporting-frame, said shaft beingprovided with a sleeve loosely held within the tilting frame, and bymeans of a shifting device operating upon a straight and a crossed beltsaid threaded shaft is rotated alternately in opposite directions tooscillate the tilting frame and move the sanding device bodily forwardand backward relatively to the work-table.

In the construction of this sandpaperingmachine I provide asupportingframe A, comprising the two side members A and A and thework-table A secured to the tops of said side members. At the rearextremities of the side members A and A and formed integral therewithare two alined hollow bearingtrunnions A within which the shaft A isrotatably mounted and upon which trunnions an upright tiltingframe, tobe hereinafter vmore fully described, is pivotally supported.

The shaft A is provided with the tight pulley A, carrying the straightand the crossed belts A and A It is also provided with the tight-pulleyA having a belt A for conveyingmotion to the upper part of the tiltingframe and with the drive-pulley A and the corresponding loose pulley AIn the forward part of the frame A a shaft A is rotatably supported.This shaft carries two loose pulleys A and A, with a tight pulley Abetween them. The pulleys A A and A are of the same diameter and areadapted to carry the straight belt A and the crossed belt A said beltsbeing thrown alternately from their loose pulleys onto the intermediatetight pulley by a belt-shifter, as. will hereinafter more fully appear.The shaft A is also provided with the miter-gear A and with a bracket Apivotally connected, by means of its bearing-sleeve A, with the shaft Ato provide a bearing for the forward The said shaft A has fixed to itsforward end a miter-gear A meshing with the gear A on the shaft A 13 isthe upright tilting frame hereinbefore mentioned. It is pivotallymounted upon the hollow trunnions A by means of the bearingopenings B atits lower end. At its upper end it is provided with similarbearing-openings l3 and intermediate its ends with aninternally-screw-threaded sleeve B adapted to receive the screw-threadedshaft A This sleeve is pivotally mounted in the tilting frame B betweenthe conical ends of two setscrews 13, and therefore is susceptible of anoscillatory or rocking movement upon said set-screws. At one side of thetilting frame B, I provide an oscillatory stud B pivotally supportedupon said frame. This stud has a transverse opening B", extendingtherethrough, adapted to receive a longitudinallymovable rod forshifting the belts A and A to change the rotative direction of thescrewthreaded shaft A 0 is said longitudinallymovable rod. It isprovided with the stopcollars 0, adjustable lengthwise of said rod bymeans of the set-screws 0 As before stated, the rod 0 passes through thetransverse opening B in the oscillatory stud B and at its forward end ispivotally connected with the bell-crank lever 0 This bell-crank lever ismounted upon a portion of the side A of the framework A. The other armof the lever is slotted to receive a pin G fixed in a shifter-rod Cmounted in bearings in said supporting-frame and adapted to be movedlongitudinally in said bearings. The shifter-rod O is provided withloops C to encircle the belts A and A to shift said belts from theirloose pulleys-to the tight pulley.

A forwardly-extending arm or frame D is provided with outwardly andoppositely extending alined hollow trunnions D. These trunnions areintended to lie within the bearing-openings B at the upper end of thetilting frame 13 and the axial openings of the trunnions to receive arotatable shaft D The shaft D has a tight pulley D thereon, intended toreceive the belt A from the pulley A; also, a tight pulley D adapted tocarry a belt D The shaft D also has fixed upon it oppositely-extendingeccentrics D. A rotatable shaft D is mounted in suitable bearings at theforward end of the arm D, the pulley D fixed thereon, being adapted toreceive the belt D passing over the pulley D. At its opposite end theshaft D has fixed a spur-pinion D adapted to mesh with a similar pinion,to be later mentioned, for rotating the sanding-drum. The arm D iscounterbalanced by means of the cord D extending upward and over thesheaves D thence passing downward and connecting with the free end of apivoted lever D the weights D slidably movable along said lever, beingadapted to properly counterbalance the weight upon the arm D.

E is a yoke secured to the forward end of the arm D by means of thebolts E. This yoke is provided with two elongated openings E throughwhich the bolts E extend, which elongated openings are intended topermit adjustment of the yoke for different sizes of spur-pinions,whereby changes in speed of the sanding-drum are obtained.

The lower arms of the yoke E are provided with alined bearing-openings Efor receiving a two-part shaft to be later described. In this instancethe bearings E are formed by inserting two brass sleeves E in suitableopenings in the arms of the yoke E, securing said sleeves in place by afilling of Babbitt metal F is said two-part shaft. It comprises twoenlarged end portions F and F and the body portion F the latter being ofa less diameter than said end portions and being formed integral withthe end portion F The end portion F is hollow and internallyscrew-threaded at its inner end to receive thecorrespondingly-screw-threaded end of the body portion F At its oppositeor outer end the end portion F is externally screwthreaded andinward ofthis screw-threading is provided with the spline F to hold a spurpinionF slotted to receive said spline and prevent said spur-pinion F fromrotation relatively to said shaft F. This spur-pinion is intended tomesh with the corresponding pinion D", fixed on the shaft D and tocommunicate rotatory motion to the sanding drum. F is said sanding-drummounted upon the body portion F of said two-part shaft F, metallicwashers F inset at the ends of the drum, providing bearing-surfaces forthe shoulders formed by the end portions F and l? of the shaft F, thuspermitting the drum to be held rigid with said shaft. The end portion Fis squared at its outer end to receive a Wrench. At each end of thesanding-drum and mounted loosely upon the brass sleeves E are twocircular disks F of a diameter substantially equal to the outer di;ameter of said drum. I form one of said disks slightly (say about onethirty-second of an inch) less in diameter than the other, the smallerdisk being intended to run upon the unsanded surface of the work as thedrum F is moved forward and backward across the table. This difierencein diameter of said disks therefore governs the depth of the out made bythe sanding-drum. Said disks also act as guards to prevent an excessivecutting away of the surface which is being smoothed by the drum.Sandpaper is wrapped around the drum F and its end held in place bymeans of the spiral binding-strip F adapted to be depressed below theperipheralsurface of the drum into a suitable channel formed in saiddrum. The strip is held in place by the screws F This spiralbinding-strip obviates the fiat side on the sanding-drum which a stripextending straight across the face of the drum would cause.

A sandpapering device for finishing flat surfaces will next bedescribed.

A yoke G of said last-mentioned device is secured upon the two-partshaft F between the lower ends of the yoke E in the same mannor as thesanding-drum is there held in place. The yoke Gis provided with twoguiderods G, upon which are supported and guided two clamping-blocks Gfor holding the sanding-blocks,to be later herein described. Theseclamping-blocks are provided with perforated ears G3 at their rear endsfor pivotally connecting said blocks with the eccentric-rods G by meansof which connection said clamping-blocks are reciprocated upon theguiderods G. The upper side of each of the clam ping-blocks issurrounded with a raised rim adapted to retain the oil which may dripfrom the guide-rods G. On their under sides the clamping-blocks areprovided at their opposite ends with the holding-ribs G and G, thelatter of which are provided with set-screws G The sanding-blocks H haveraised middle portions adapted to enter between the ribs G and G6 of theunder side of the clamping-block G2 and be held in position between saidribs by an adjustment of the set-screws G The lower portion or body ofeach of the sanding-blocks is provided at its inner and outer edges withchannels adapted to receive the half-round metallic pieces H, perforatedat their ends to receive the clamping-rods H and H each of which rods isthreaded at its ends and provided with a wing-nut H The inner ends-ofthe blocks H are tapered, so that they may overlap and no unsandedportion shall remain between them when the machine is in operation.Sandpaper is removed from the rubbing-blocks H by unscrewing thewing-nuts H and removing the frame composed of the half-round bars H andtheir clamping-rods H To put sandpaper upon the rubbing-blocks, a pieceof a suitable size is cut and folded over the lower face of the blocksH. The bars H are then placed against the sandpaper at the forward andrear edges of the rubbing-blocks,the rods H put through the perforationsin the ends of said bars, and the bars drawn into their grooves in theedges of the blocks by tightening the wing-nuts H The rubbing-blocks Hare formed with diagonally-cut inner ends. This prevents their passingone another, but insures the sanding of the entire surface over whichthey travel, which would not be the case ifalongitudinal space were leftbetween their adjacent ends. Arms Hiextending downward from the yoke E,are provided with set-screws Hf, passing through threaded openings inthe outer ends of said arms. These set-screws bear upon opposite ends ofthe yoke G and prevent the oscillation of the latter upon the two-partshaft F. They also permit an adj ustment of the position of the yoke G,so that the sanding-blocks may be caused to reciprocate in a plane at anangle with the surface of the work-table 1n the operation of thissandpapering-machine rotatory motion is imparted to the sanding-drum Ffrom the drive-pulley A. Said drum will be reciprocated forward and backover the work-table by the tilting frame B, said frame being movedforward by the rotation of the screw-threaded shaft A until theoscillatory stud 13 engages the stop-collar C tion.

and pushes the rod 0 forward, shifting the straight belt A from thetight pulley A and throwing the crossed belt A upon said tight pulley.This reverses the motion of the screwthreaded shaft A and causes thetilting frame B to be oscillated in a contrary direc- The frame movesbackward until the oscillatory stud 13 engages the rear stop-collar O onthe rod 0 and pulls said rod rearward, shifting the crossed belt fromthe tight pulley and throwing the straight belt upon said tight pulley,again changing the rotative direction of said screw-threaded shaft andmoving the tilting frame forward.

The amount of downward pressure of the sanding-drum is regulated bymoving the weights D longitudinally of the pivoted lever D They may beplaced so that a considerable downward pressure will be exerted by thedrum upon the work or in such a manner that the drum will bear butlightly upon the surface being sanded. Sandpaper is held upon the drumby means of the binding-strip F placed in the channel extendingdiagonally across the peripheral surface of said drum. The diagonalposition of the bindingstrip does away with a flat face or indentationin said drum, which would be caused by the strip were it placed parallelwith the drums axis. Spur-pinions F of diiferent size may be used tochange the speed of ro tation of the sanding-drum, the yoke E beingadjusted to obtain the proper engagement between the spnr-gear D andsaid gear F When a flat surface is to be sanded, the sanding-drum F isremoved by separating the parts F and F of the shaft F, removing thedrum therefrom, and substituting the yoke G, passing the shaft F throughthe perforations in said yoke adapted for its reception. If the work islevel, the plane of the guide-rods G is adjusted by means of theset-screws H The eccentric-rods G are then connected with theclamping-blocks G at the forward ends of said eccentric-rods and to theeccentrics D at the rear ends of said rods. Sandpaper is folded over therubbingblocks H, and said blocks are held firmly in the clamping-blocksby means of the set screws G When motion is imparted to the machinery,the rubbing-blocks H are rapidly reciprocated forward and backward bymeans of their connection with the eccentrics D on the shaft D and thesanding device is bodily reciprocated forward and backward over thework-table by means of the reversal of the rotative direction of thescrew-threaded shaft A The sanding-drum is employed for uneven surfaces,the diameter of the drum being made suitable for the curves of the workto be done.

The amplitude of the forward-and-back movement of the sanding device(either the drum F or the sanding-blocks H) is regulated by the positionof the stop-collars C on the rod 0. If the stop-collars are near together, the amplitude of the forward-and- IIO back movement of thesanding device will be small, but if far apart said amplitude Will besufficient to include the length of the Worktable A While Ihavedescribed my invention in its application to sandpapering-machines, itis clear that it may be embodied in apparatus for polishing or abradingglass, stone, metal, or other material.

I claim as my invention 1. In a sandpapering-machine, in combination, asupporting-frame; a tilting frame pivotally mounted with relation tosaid supporting-frame; a sandpapering device supported by said tiltingframe; means for actuating said sandpapering device; a screw-threadedshaft having a connection With said tilting frame and means for rotatingsaid shaft to oscillate said frame and reciprocate the sanding devicewith relation to the supportingframe.

2. In a sandpapering-machine, in combina tion, a supporting-frame; atilting frame pivotally mounted with relation to said supporting-frame;an arm having a pivotal connection with said tilting frame; asandpapering device supported by said arm; means for actuating saidsandpapering device; a screwthreaded shaft having a connection With saidtilting frame; and means for rotating said shaft to oscillate saidtilting frame and reciprocate the sanding device relatively to thesupporting-frame.

3. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted With relation to said supporting-frame;.a sandpapering device supported by said tilting frame; means foractuating said sandpapering device; a screw-threaded shaft havingconnection With said tilting frame; means for rotating said shaft inopposite directions; and means adapted to be operated by the movement ofsaid tilting frame for changing the rotative direction of saidscrew-threaded shaft.

4;. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted With relation to said supporting-frame;a sandpapering device supported by said tilting frame; means foractuating said sandpapering device; a shaft having a screw-threadengagement with a portion of said tilting frame; means for rotating saidshaft in opposite directions; and means adapted to be operated by themovement of said tilting frame for changing the rotative direction ofsaid shaft.

5. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device; means for supporting the sandpaperin g device;means for reciprocating the sandpapering device with relation to itssupporting means; and means for reciprocating said supporting means withrelation to the frame.

6. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device; an arm for supporting said sandpapering device;means for reciprocating said sand- 'papering device With relation tosaid arm; and means for reciprocating said arm with relation to saidsupporting-frame.

7. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device; an arm for supporting said sandpapering device;means for reciprocating the sandpapering device with relation to saidarm; a tilting frame for reciprocating said arm with relation to thesupporting-frame; and means for oscillating said tilting frame.

8. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device; an arm for supporting said sandpapering device;means for reciprocating said sandpaper-ing device with relation to saidarm; a tilting frame for reciprocating said arm with relation to thesupporting-frame; a shaft having a screw-thread engagement with saidtilting frame; and means for rotating said shaft in opposite directions.

9. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device; an arm for supporting said sandpapering device;means for reciprocating the sand papering device with relation to thearm; a

tilting frame for reciprocating said arm with relation to thesupporting-frame a shaft having a screw-thread engagement with saidtilting frame; means for rotating said shaft; and means adapted to beoperated by the movement of said tilting frame for changing the rotativedirection of said shaft.

10. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device having a plurality of independent abrading-surfaces;means for supporting the sandpapering device; means for reciprocatingsaid independent abradin -surfaces in contrary directions with relationto each other; and means for reciprocating said supporting means withrelation to the frame.

11. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device having a plurality of independent abrading-surfaces;an arm for supporting said sandpapering device; meansfor reciprocatingsaid independent abrading-surfaces in contrary directions with relationto each other; a tilting frame for reciprocating said arm with relationto the supporting-frame; and means for oscillating said tilting frame.

12. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device having a plurality of independent abrading-surfaces;an arm for supporting said sandpapering device; means for reciprocatingsaid independent abrading-surfaces in con trary directions with relationto each other; a tilting frame for reciprocating said arm with relationto the supporting-frame a shaft having a screw-thread engagement withsaid tilting frame; and means for rotating said shaft in oppositedirections.

13. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device having a plurality of independent abradingsurfaces;an arm for supporting said sandpapering device; means for reciprocatingthe independent abrading-surfaces in contrary directions with relationto each other a tilting frame for reciprocating said arm with relationto the supporting-frame; a shaft having a screw-thread engagement withsaid tilting frame; means for rotating said shaft; and means adapted tobe operated by the movement of said tilting frame for changing therotative direction of said shaft.

14. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device having a plurality of rubbing-blocks; an arm forsupporting said sandpapering device; guides for said rubbing-blocks;means for moving said rubbing-blocks upon said guides in contrarydirections with relation. to each other; a tilting frame forreciprocating said arm with relation to the supportingframe; 7 a shafthaving a screw-thread engagement with said tilting frame; means forrotating said shaft; and-means adapted to be operated by the movement ofsaid tilting frame for changing the rotative direction of said shaft.

15. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device having a plurality of rubbing-blocks; an arm forsupporting said sandpapering device; a guide-rod for each of saidrubbingblocks; two oppositely-extending eccentrics; eccentric-rodsconnecting said eccentrics with said rubbing-blocks; means for rotatingsaid eccentrics to move said rubbing-blocks upon said guide-rods; atilting frame for reciprocating said arm with relation to thesupporting-frame; a shaft having a screw-thread engagement with saidtilting frame; means for rotating said shaft; and means adapted to beoperated by the movement of said tilting frame for changing the rotativedirection of said shaft.

16. In a sandpaperingmachine, in combination, a supporting-frame; asandpapering device comprising two rubbing-blocks; means forreciprocating said blocks in contrary directions with relation to eachother; and means for bodily moving the sandpapering device forward andbackward with relation to the supporting-frame.

17. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device comprising two rubbing-blocks, the adjacent edges ofwhich rubbing-blocks are formed at an angle with the line of movement ofsaid blocks; and means for reciprocating said blocks in contrarydirections with relation to each other.

18. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device comprising two rubbing-blocks, the adjacent edges ofwhich rubbing-blocks are formed at an angle with the line of movement ofsaid blocks guides for said rubbing-blocks;

and means for moving said rubbing-blocks in opposite directions uponsaid guides.

19. In a sandpapering-machine, iu combination, a supporting-frame; asandpapering device comprising two rubbing-blocks, the adjacent edges ofwhich rubbing blocks are formed at an angle with the line of movement ofsaid blocks; guides for said rubbing-blocks; means for moving saidrubbing-blocks in opposite directions upon said guides; and means forreciprocating the sandpapering device bodily forward and backward.

20. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device comprising two rubbing-blocks, the ad jacent edgesof which are formed at an angle with the line of movement of saidblocks; an eccentric for reciprocatingone of said rubbingblocks; atilting frame for moving said sandpapering device bodily forward andbackward; means for rotating said eccentrics; and means for oscillatingsaid tilting frame.

21. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted with relation to said supporting-frame;a sandpapering device supported by said tilting frame; means foractuating said sandpapering device; a counterbalance-lever for saidsandpapering device; a shaft having a screw-thread engagement with aportion of said tilting frame; means for rotating said shaft in oppositedirections; and means adapted to be operated by the movement of saidtilting frame for changing the rotative direction of said shaft.

22. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted with relation to said supporting-frame;a pivoted arm connected with said tilting frame; a sandpapering devicemounted on said pivoted arm; an eccentric for actuating saidsandpapering device; a shaft having a screw-thread engagement with aportion of said tilting frame; means for rotating said shaft in oppositedirections; and means adapted to be operated by the movement of saidtilting frame, for changing the rotative direction of said shaft.

In a sandpapering-machine, in combination, a supporting-frame; a tiltingframe pivotally mounted with relation to said supporting-frame; an armpivotally connected with said tilting frame; a sandpapering devicemounted on said arm; two eccentrics for actuating said sandpaperingdevice; a counterbalance-lever for said sandpapering device; aconnection between the pivoted arm and said counterbalance-lever a shafthaving a screwthread engagement with a portion of said tilting frame;means for rotating said shaft in opposite directions; and means adaptedto be operated by the movement of said tilting frame for changing therotative direction ofsaid shaft.

24:. In a sandpapering-machine, in combination, a supporting-frame; atilting frame IIO pivotally mounted with relation to saidsupporting-frame; a sandpapering device supported by said tilting frame,which sandpapering device comprises two rubbing-blocks; means forreciprocating said rubbing-blocks in contrary directions with relationto each other; and means for oscillating said tilting frame to move thesandpapering device bodily forward and backward.

25. In a sandpaperingmachine, in combination, a supporting-frame; atilting frame pivotally mounted with relation to said supporting-frame;an arm pivotally connected with said tilting frame; a sandpaperingdevice supported by said arm, said sandpaper ing device comprising tworubbing-blocks; means for reciprocating said. rubbing-blocks in contrarydirections with relation to each other; a shaft having a screw-threadconnection with said tilting frame; and means for rotating said shaft inopposite directions to oscillate said tilting frame and move saidsandpapering device bodily forward and back- Ward.

26. In a sandpapering-machine, in combination, a supporting-frame; awork-table thereon; a tilting frame pivotally mounted with relation tosaid supporting-frame; an arm pivotally connected with said tiltingframe; a sandpapering device supported by said arm, which sandpaperingdevice comprises two rubbing-blocks; means for reciprocating saidrubbing-blocks in contrary directions with relation to each other; and ashaft havinga screwthread engagement with said tilting frame, whichshaft is adapted to be rotated in opposite directions to oscillate saidtilting frame and move said sandpapering device forward and backwardover said work-table.

27. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted with relation to said supportingframe;an arm pivotally connected with said tilting frame; a sandpaperingdevice supported by said arm, which sandpapering device comprises tworubbingblocks; a shaft at the pivotal connection between the tiltingframe and the arm pivotally mounted thereon; two eccentrics fixed onsaid shaft; eccentric-rods for connecting said eccentrics with saidrubbing-blocks; a shaft having a screw-thread engagement with saidtilting frame, which shaft is adapted to be rotated in oppositedirections to oscillate said tilting frame and move said sandpaperingdevice forward and backward over said su pportingframe.

28. In a sandpapering-machine, in combination, asupporting-frame; atilting frame pivotally mounted with relation to said supporting-frame;an arm pivotally connected with said tilting frame; a sandpaperingdevice comprising two rubbing-blocks and a guide for each of saidrubbing-blocks; a twopart shaft for pivotally connecting saidsandpapering device to the free end of said pivoted arm; a weightedlever for counterbalroaaaa ancing the sandpapering device; a shaftmounted in the supporting-frame, having a screw thread connection withsaid tilting frame; and means for rotating said shaft in oppositedirections to oscillate said tilting frame and move the sandpaperingdevice bodily forward and backward.

29. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted with relationto said supporting-frame;an arm pivotally connected with said tilting frame; a sandpaperingdevice supported by said arm, said sandpapering device comprising tworubbing-blocks and a guide-rod for each of said rubbing-blocks; atwo-part shaft for pivotally connecting said sandpapering device to thefree end of said pivoted arm; a shaft at the pivotal connection betweenthe tilting frame and the arm pivotally mounted thereon; twooppositely-extending eccentrics fixed on said shaft; eccentricrodsconnecting said eccentrics with said rubbing-blocks; a shaft mounted inthe supporting-frame and having a screw-thread connection with saidtilting frame; and a crossed belt and a straight belt adapted to rotatesaid shaft in opposite directions to oscillate said tilting frame andmove the sandpapering device bodily forward and backward.

30. In a sandpapering-machine, in combination, a supporting-frame; asandpapering device comprising a yoke, two guide-rods fixed in saidyoke, and rubbing-blocks slidably mounted upon each of said guide-rods,the adjacent edges of said rubbing-blocks being formed at an angle withtheir line of movement, straps at the sides of each of said blocks forsecuring sandpaper upon the blocks, and rods for connecting said strapstogether at the ends of the latter; two eccentrics; an eccentric-rodextending between each of said eccentrics and one of saidrubbing-blocks; a tilting frame for supporting the sandpapering device;means for rotating said eccentrics; and means for oscillating saidtilting frame.

31. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted with relation to said supporting-frame;an arm having a pivotal connection with said tilting frame; asandpapering device supported by said arm; a weighted lever forcounterbalancing the sandpapering device; a flexible connectionextending between said pivoted arm and said weighted lever; a shaftmounted in said supportingframe, having a screw-thread connection withsaid tilting frame; a straight and a crossed belt for rotating saidshaft alternately in opposite directions; a shifting device for saidbelts; means on the tilting frame for operatin g said shifting device tochange the rotative direction of said shaft; and means for actuatingsaid sandpapering device.

32. In a sandpapering-machine, in combination, a supporting-frame; atilting frame pivotally mounted with relation to said supporting-frame;an arm having a pivotal contilting frame; a straight and a crossed beltfor rotating said shaft in contrary directions; a

shifting device for said belts, the rod for operating said shiftingdevice extending through a stud upon said tilting frame; and adjust- Iable stops mounted on said rod and adapted to be engaged by said stud.

JOHN A. HALLDEN. Vitnesses:

L. L. MILLER, GEo. L. CHINDAHL.

